Carlo Rovelli

Instant New York Times Bestseller "Short and resonant. . . . The essays in Seven Brief Lessons on Physics arrive like shots of espresso."--The New York Times "A startling and illustrative distillation of centuries of science."--The Economist "Lean, lucid and enchanting."--New Scientist The international bestseller that reveals all the beauty of modern physics in seven short and enlightening lessons Seven Brief Lessons on Physics is a book about the joy of discovery. Carlo Rovelli brings a playful, entertaining, and mind-bending introduction to modern physics, offering surprising--and surprisingly easy to grasp--explanations of Einstein's general relativity, quantum mechanics, elementary particles, gravity, black holes, the complex architecture of the universe, and the role humans play in this weird and wonderful world. He takes us to the frontiers of our knowledge: to the most minute reaches of the fabric of space, back to the origins of the cosmos, and into the workings of our minds. "Here, on the edge of what we know, in contact with the ocean of the unknown, shines the mystery and the beauty of the world," Rovelli writes. "And it's breathtaking."

Seven Brief Lessons on Physics

Amelia

In both cases the reward is sheer beauty and new eyes with which to see the world.

Before experiments, measurements, mathematics, and rigorous deductions, science is above all about visions. Science begins with a vision. Scientific thought is fed by the capacity to "see" things differently than they have previously been seen.

Even if we observe a small, empty region of space in which there are no atoms, we still detect a minute Swarming of these particles. There is no such thing as a real void, one that is completely empty. Just as the calmest sea looked at closely sways and trembles, however slightly, so the fields that form the world are subject to minute fluctuations, and it is possible to imagine its basic particles having brief and ephemeral existences, continually created and destroyed by these movements.

Our world may have actually been born from a preceding universe that contracted under its own weight until it was squeezed into a tiny space before "bouncing" out and beginning to re-expand, thus becoming the expanding universe that we observe around us. The moment of this bounce, when the universe was contracted into a nutshell, is the true realm of quantum gravity: time and space have disappeared altogether, and the world has dissolved into a swarming cloud of probability that the equations can, however, still describe. 

The difference between past and future exists only when there is heat. The fundamental phenomenon that distinguishes the future from the past is the fact that heat passes from things that are hotter to things that are colder.

Another way of posing the problem is to ask oneself: what is the "present"? We say that only the things of the present exist: the past no longer exists and the future doesn't exist yet. But in physics there is nothing that corresponds to the notion of the "now." Compare "now" with "here." "Here" designates the place where a speaker is: for two different people "here" points to two different places. Consequently "here" is a word the meaning of which depends on where it is spoken. The technical term for this kind of utterance is "indexical." "Now" also points to the instant in which the word is uttered and l5 also classed as indexical." But no one would dream Of saying that things "here" exist, whereas things that are not "here" do nọt exİSt. So then why do we say that things that are now exist and that everything else đoesn’t? 

The heat of black holes is a quantum effect upon an object, the black hole, which is gravitational in nature. It is the individual quanta of space, the elementary grains of space, the vibrating "molecules," that heat the surface of black holes and generate black hole heat. This phenomenon involves all three sides of the problem: quantum mechanics, general relativity, and thermal science. The heat of black holes is like the Rosetta stone of physics, written in a combination of three languages quantum, gravitational, and thermodynamicstill awaiting decipherment in order to reveal the true nature of time.

Our intense sensation of interior liberty, as Spinoza acutely saw, comes from the fact that the ideas and images that we have of ourselves are much cruder and sketchier than the detailed complexity of what is happening within us. We are the source of amazement in our own eyes. 

We have a hundred billion neurons in our brains, as many as there are stars in a galaxy, with an even more astronomical number of links and potential combinations through which they can interact. We are not conscious of all of this. "We are the process formed by this entire intricacy, not just by the little of it of which we are conscious. The "I" who decides is that same "T" that is formed (in a way that is still certainly not completely clear, but that we have begun to glimpse) from reflections upon itself, through self-representations in the world, from understanding itself as a variable point of view placed in the context of the world, from that impressive structure that processes information and constructs repre sentations that is our brain. When we have the feeling that "it is I" who decides, we couldn't be more correct. Who else?

Here, on the edge of what we know, in contact with the ocean of the unknown, shines the mystery and the beauty of the world. And it's breathtaking.

Seven Brief Lessons on Physics quotes

Join the club